The rights group says more than 100 others are on death row. Many of them are foreigners.

The group highlighted the case of two brothers sentenced to death in 1998 for murder and at "imminent risk of execution." Amnesty says they had no access to lawyers.

"However strongly the Saudi Arabian authorities support the death penalty, they must at least recognize that no one should be executed after such problematic legal proceedings and commute their death sentences," said Philip Luther, Amnesty International's Deputy Director for the Middle East and North Africa.

Saudi Arabia follows a strict interpretation of Islam under which people convicted of murder, drug trafficking, rape and armed robbery can be executed - usually with a sword.